1# @(#)northamerica 7.28
2# also includes Central America and the Caribbean
3
4# This data is by no means authoritative; if you think you know better,
5# go ahead and edit the file (and please send any changes to
6# tz@elsie.nci.nih.gov for general use in the future).
7
8# From Paul Eggert <eggert@twinsun.com> (1994-08-17):
9# A reliable and entertaining source about time zones is
10# Derek Howse, Greenwich time and the discovery of the longitude,
11# Oxford University Press (1980).
12
13###############################################################################
14
15# United States
16
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36# scheme I detect the bony, blue-fingered hand of Puritanism, eager
37# to push people into bed earlier, and get them up earlier, to make
38# them healthy, wealthy and wise in spite of themselves.
39#
40# -- Robertson Davies, The Diary of Samuel Marchbanks (1947), XIX, Sunday
41
42# From Arthur David Olson:
43# US Daylight Saving Time ended on the last Sunday of *October* in 1974.
44# See, for example, the front page of the Saturday, 1974-10-26
45# and Sunday, 1974-10-27 editions of the Washington Post.
46
47# From Arthur David Olson:
48# Before the Uniform Time Act of 1966 took effect in 1967, observance of
49# Daylight Saving Time in the US was by local option, except during wartime.
50
51# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
52Rule US 1918 1919 - Mar lastSun 2:00 1:00 W # War
53Rule US 1918 1919 - Oct lastSun 2:00 0 S
54Rule US 1942 only - Feb 9 2:00 1:00 W # War
55Rule US 1945 only - Sep 30 2:00 0 S
56Rule US 1967 max - Oct lastSun 2:00 0 S
57Rule US 1967 1973 - Apr lastSun 2:00 1:00 D
58Rule US 1974 only - Jan 6 2:00 1:00 D
59Rule US 1975 only - Feb 23 2:00 1:00 D
60Rule US 1976 1986 - Apr lastSun 2:00 1:00 D
61Rule US 1987 max - Apr Sun>=1 2:00 1:00 D
62
63# From Bob Devine (1988-01-28):
64# ...Alaska (and Hawaii) had the timezone names changed in 1967.
65# old new
66# Pacific Standard Time(PST) -same-
67# Yukon Standard Time(YST) -same-
68# Central Alaska S.T. (CAT) Alaska-Hawaii St[an]dard Time (AHST)
69# Nome Standard Time (NT) Bering Standard Time (BST)
70#
71# ...Alaska's timezone lines were redrawn in 1983 to give only 2 tz.
72# The YST zone now covers nearly all of the state, AHST just part
73# of the Aleutian islands. No DST.
74
75# From Paul Eggert (1995-12-19):
76# The tables below use `NST', not `NT', for Nome Standard Time.
77# I invented `CAWT' for Central Alaska War Time.
78
79# From U. S. Naval Observatory (1989-01-19):
80# USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON
81# USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30
82# USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON
83# USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30
84# USA MOUNTAIN 7 H BEHIND UTC DENVER
85# USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30
86# USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO
87# USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30
88# USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST)
89# USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT)
90# USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W
91# USA - " - 9 H BEHIND UTC APR 3 - OCT 30
92# USA HAWAII 10 H BEHIND UTC
93# USA BERING 11 H BEHIND UTC SAMOA, MIDWAY
94
95# From Arthur David Olson (1989-01-21):
96# The above dates are for 1988.
97# Note the "AKST" and "AKDT" abbreviations, the claim that there's
98# no DST in Samoa, and the claim that there is DST in Alaska and the
99# Aleutians.
100
101# From Arthur David Olson (1988-02-13):
102# Legal standard time zone names, from United States Code (1982 Edition and
103# Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names
104# up to 1967-04-01 (when most provisions of the Uniform Time Act of 1966
105# took effect), as explained in sections 263 and 261:
106# (none)
107# United States standard eastern time
108# United States standard mountain time
109# United States standard central time
110# United States standard Pacific time
111# (none)
112# United States standard Alaska time
113# (none)
114# Next, names from 1967-04-01 until 1983-11-30 (the date for
115# public law 98-181):
116# Atlantic standard time
117# eastern standard time
118# central standard time
119# mountain standard time
120# Pacific standard time
121# Yukon standard time
122# Alaska-Hawaii standard time
123# Bering standard time
124# And after 1983-11-30:
125# Atlantic standard time
126# eastern standard time
127# central standard time
128# mountain standard time
129# Pacific standard time
130# Alaska standard time
131# Hawaii-Aleutian standard time
132# Samoa standard time
--- 12 unchanged lines hidden (view full) ---
145Rule NYC 1955 1966 - Oct lastSun 2:00 0 S
146# Zone NAME GMTOFF RULES FORMAT [UNTIL]
147Zone America/New_York -4:56:02 - LMT 1883 Nov 18 12:00
148 -5:00 US E%sT 1920
149 -5:00 NYC E%sT 1942
150 -5:00 US E%sT 1946
151 -5:00 NYC E%sT 1967
152 -5:00 US E%sT
153
154# US Central time, represented by Chicago
155# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
156Rule Chicago 1920 only - Jun 13 2:00 1:00 D
157Rule Chicago 1920 1921 - Oct lastSun 2:00 0 S
158Rule Chicago 1921 only - Mar lastSun 2:00 1:00 D
159Rule Chicago 1922 1966 - Apr lastSun 2:00 1:00 D
160Rule Chicago 1922 1954 - Sep lastSun 2:00 0 S
161Rule Chicago 1955 1966 - Oct lastSun 2:00 0 S
162# Zone NAME GMTOFF RULES FORMAT [UNTIL]
163Zone America/Chicago -5:50:36 - LMT 1883 Nov 18 12:00
164 -6:00 US C%sT 1920
165 -6:00 Chicago C%sT 1936 Mar 1 2:00
166 -5:00 - EST 1936 Nov 15 2:00
167 -6:00 Chicago C%sT 1942
168 -6:00 US C%sT 1946
169 -6:00 Chicago C%sT 1967
170 -6:00 US C%sT
171
172# US Mountain time, represented by Denver
173# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
174Rule Denver 1920 1921 - Mar lastSun 2:00 1:00 D
175Rule Denver 1920 only - Oct lastSun 2:00 0 S
176Rule Denver 1921 only - May 22 2:00 0 S
177Rule Denver 1965 1966 - Apr lastSun 2:00 1:00 D
178Rule Denver 1965 1966 - Oct lastSun 2:00 0 S
179# Zone NAME GMTOFF RULES FORMAT [UNTIL]
180Zone America/Denver -6:59:56 - LMT 1883 Nov 18 12:00
181 -7:00 US M%sT 1920
182 -7:00 Denver M%sT 1942
183 -7:00 US M%sT 1946
184 -7:00 Denver M%sT 1967
185 -7:00 US M%sT
186
187# US Pacific time, represented by Los Angeles
188# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
189Rule CA 1948 only - Mar 14 2:00 1:00 D
190Rule CA 1949 only - Jan 1 2:00 0 S
191Rule CA 1950 1966 - Apr lastSun 2:00 1:00 D
192Rule CA 1950 1961 - Sep lastSun 2:00 0 S
193Rule CA 1962 1966 - Oct lastSun 2:00 0 S
194# Zone NAME GMTOFF RULES FORMAT [UNTIL]
195Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 12:00
196 -8:00 US P%sT 1946
197 -8:00 CA P%sT 1967
198 -8:00 US P%sT
199
200# Alaska
201# AK%sT is the modern abbreviation for -9:00 per USNO.
202#
203# From Paul Eggert (1995-12-19):
204# Howse writes that Alaska switched from the Julian to the Gregorian calendar,
205# and from east-of-GMT to west-of-GMT days, when the US bought it from Russia.
206# This was on 1867-10-18. We omit this transition, since we can't represent
207# changes from Julian to Gregorian.
208#
209# Zone NAME GMTOFF RULES FORMAT [UNTIL]
210Zone America/Juneau -8:57:41 - LMT 1900 Aug 20 12:00
211 -8:00 - PST 1942
212 -8:00 US P%sT 1946
213 -8:00 - PST 1969
214 -8:00 US P%sT 1983 Oct 30 2:00
215 -9:00 US AK%sT
--- 24 unchanged lines hidden (view full) ---
240 -11:00 - BST 1969
241 -11:00 US B%sT 1983 Oct 30 2:00
242 -10:00 US HA%sT
243# Shanks writes that part of southwest Alaska (e.g. Aniak)
244# switched from -11:00 to -10:00 on 1968-09-22 at 02:00,
245# and another part (e.g. Akiak) made the same switch five weeks later.
246# These switches don't quite make our 1970 cutoff.
247
248# Hawaii
249#
250# From Arthur David Olson:
251# And then there's Hawaii.
252# DST was observed for one day in 1933;
253# standard time was changed by half an hour in 1947;
254# it's always standard as of 1986.
255#
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262 -10:30 US H%sT 1947 Jun 8 2:00
263 -10:00 - HST
264
265Zone Pacific/Midway -11:49:28 - LMT 1901
266 -11:00 - NST 1967 Apr # N=Nome
267 -11:00 - BST 1983 Nov 30 # B=Bering
268 -11:00 - SST # S=Samoa
269
270# Now we turn to US areas that have diverged from the consensus since 1970.
271
272# Arizona mostly uses MST.
273Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 12:00
274 -7:00 US M%sT 1944 Jan 1 00:01
275 -7:00 - MST 1944 Mar 17 00:01
276 -7:00 US M%sT 1944 Oct 1 00:01
277 -7:00 - MST 1967
278 -7:00 US M%sT 1968
279 -7:00 - MST
280# From Arthur David Olson (1988-02-13):
281# A writer from the Inter Tribal Council of Arizona, Inc.,
282# notes in private correspondence dated 12/28/87 that "Presently, only the
283# Navajo Nation participates in the Daylight Saving Time policy, due to its
284# large size and location in three states." (The "only" means that other
285# tribal nations don't use DST.)
286
287Link America/Denver America/Shiprock
288
289# Southern Idaho and eastern Oregon switched four weeks late in 1974.
290# Zone NAME GMTOFF RULES FORMAT [UNTIL]
291Zone America/Boise -7:44:49 - LMT 1883 Nov 18 12:00
292 -8:00 US P%sT 1923 May 13 2:00
293 -7:00 US M%sT 1974
294 -7:00 - MST 1974 Feb 3 2:00
295 -7:00 US M%sT
296
297# Indiana
298#
299# From Paul Eggert (1995-12-19):
300# Indiana generally observes either EST all year, or CST/CDT,
301# but areas near Cincinnati and Louisville use those cities' timekeeping
302# and in 1969 and 1970 the whole state observed daylight time;
303# and there are other exceptions as noted below.
304# Shanks partitions Indiana into 345 regions, each with its own time history,
--- 21 unchanged lines hidden (view full) ---
326 -6:00 US C%sT 1946
327 -6:00 Indianapolis C%sT 1955 Apr 24 2:00
328 -5:00 - EST 1957 Sep 29 2:00
329 -6:00 - CST 1958 Apr 27 2:00
330 -5:00 - EST 1969
331 -5:00 US E%sT 1971
332 -5:00 - EST
333Link America/Indianapolis America/Indiana/Indianapolis
334#
335# Part of Crawford County, Indiana, last observed DST in 1975,
336# and left its clocks alone in 1974.
337# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
338Rule Marengo 1951 only - Apr lastSun 2:00 1:00 D
339Rule Marengo 1951 only - Sep lastSun 2:00 0 S
340Rule Marengo 1954 1960 - Apr lastSun 2:00 1:00 D
341Rule Marengo 1954 1960 - Sep lastSun 2:00 0 S
342# Zone NAME GMTOFF RULES FORMAT [UNTIL]
343Zone America/Indiana/Marengo -5:45:23 - LMT 1883 Nov 18 12:00
344 -6:00 US C%sT 1951
345 -6:00 Marengo C%sT 1961 Apr 30 2:00
346 -5:00 - EST 1969
347 -5:00 US E%sT 1974 Jan 6 2:00
348 -6:00 1:00 CDT 1974 Oct 27 2:00
349 -5:00 US E%sT 1976
350 -5:00 - EST
351#
352# Starke County, Indiana
353# From Arthur David Olson (1991-10-28):
354# An article on page A3 of the Sunday, 1991-10-27 Washington Post
355# notes that Starke County switched from Central time to Eastern time as of
356# 1991-10-27.
357# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
358Rule Starke 1947 1961 - Apr lastSun 2:00 1:00 D
359Rule Starke 1947 1954 - Sep lastSun 2:00 0 S
360Rule Starke 1955 1956 - Oct lastSun 2:00 0 S
361Rule Starke 1957 1958 - Sep lastSun 2:00 0 S
362Rule Starke 1959 1961 - Oct lastSun 2:00 0 S
363# Zone NAME GMTOFF RULES FORMAT [UNTIL]
364Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 12:00
365 -6:00 US C%sT 1947
366 -6:00 Starke C%sT 1962 Apr 29 2:00
367 -5:00 - EST 1963 Oct 27 2:00
368 -6:00 US C%sT 1991 Oct 27 2:00
369 -5:00 - EST
370#
371# Switzerland County, Indiana, last observed DST in 1972.
372# Zone NAME GMTOFF RULES FORMAT [UNTIL]
373Zone America/Indiana/Vevay -5:40:16 - LMT 1883 Nov 18 12:00
374 -6:00 US C%sT 1954 Apr 25 2:00
375 -5:00 - EST 1969
376 -5:00 US E%sT 1973
377 -5:00 - EST
378
379# Part of Kentucky left its clocks alone in 1974.
380# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
381Rule Louisville 1921 only - May 1 2:00 1:00 D
382Rule Louisville 1921 only - Sep 1 2:00 0 S
383Rule Louisville 1941 1961 - Apr lastSun 2:00 1:00 D
384Rule Louisville 1941 only - Sep lastSun 2:00 0 S
385Rule Louisville 1946 only - Jun 2 2:00 0 S
386Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S
--- 4 unchanged lines hidden (view full) ---
391 -6:00 Louisville C%sT 1942
392 -6:00 US C%sT 1946
393 -6:00 Louisville C%sT 1961 Jul 23 2:00
394 -5:00 - EST 1968
395 -5:00 US E%sT 1974 Jan 6 2:00
396 -6:00 1:00 CDT 1974 Oct 27 2:00
397 -5:00 US E%sT
398
399# Michigan
400#
401# From Bob Devine (1988-01-28):
402# Michigan didn't observe DST from 1968 to 1973.
403#
404# From Paul Eggert (1995-12-19):
405# Shanks writes that Michigan started using standard time on 1885 Sep 18,
406# but Howse (p 126) writes that Detroit kept
407#
408# local time until 1900 when the City Council decreed that clocks should
409# be put back twenty-eight minutes to Central Standard Time. Half the
--- 15 unchanged lines hidden (view full) ---
425Zone America/Detroit -5:32:11 - LMT 1905
426 -6:00 - CST 1915 May 15 2:00
427 -5:00 - EST 1942
428 -5:00 US E%sT 1946
429 -5:00 Detroit E%sT 1973
430 -5:00 US E%sT 1975
431 -5:00 - EST 1975 Apr 27 2:00
432 -5:00 US E%sT
433#
434# The Michigan border with Wisconsin switched from EST to CST/CDT in 1973.
435# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
436Rule Menominee 1946 only - Apr lastSun 2:00 1:00 D
437Rule Menominee 1946 only - Sep lastSun 2:00 0 S
438Rule Menominee 1966 only - Apr lastSun 2:00 1:00 D
439Rule Menominee 1966 only - Oct lastSun 2:00 0 S
440# Zone NAME GMTOFF RULES FORMAT [UNTIL]
441Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00
442 -6:00 US C%sT 1946
443 -6:00 Menominee C%sT 1969 Apr 27 2:00
444 -5:00 - EST 1973 Apr 29 2:00
445 -6:00 US C%sT
446
447# Navassa
448# uninhabited
449
450
451# Old names, for S5 users
452
453# Link LINK-FROM LINK-TO
454Link America/New_York EST5EDT
455Link America/Chicago CST6CDT
456Link America/Denver MST7MDT
457Link America/Los_Angeles PST8PDT
458Link America/Indianapolis EST
459Link America/Phoenix MST
460Link Pacific/Honolulu HST
461
462################################################################################
463
464
465# From Paul Eggert <eggert@twinsun.com> (1993-11-18):
466# A good source for time zone historical data outside the US is
467# Thomas G. Shanks, The International Atlas (3rd edition),
468# San Diego: ACS Publications, Inc. (1991).
469# Except where otherwise noted, it is the source for the data below.
470#
471# Another source occasionally used is Edward W. Whitman, World Time Differences,
472# Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated), which
473# I found in the UCLA library.
474#
475# See the `europe' file for Greenland.
476#
477# See the `africa' file for time zone naming and abbreviation conventions.
478
479# Canada
480
481# From Alain LaBont<e'> <ALB@immedia.ca> (1994-11-14):
482# I post here the time zone abbreviations standardized in Canada
483# for both English and French in the CAN/CSA-Z234.4-89 standard....
484#
485# UTC Standard time Daylight savings time
--- 72 unchanged lines hidden (view full) ---
558Rule StJohns 1988 only - Apr Sun>=1 2:00 2:00 DD
559Rule StJohns 1989 max - Apr Sun>=1 2:00 1:00 D
560# St John's has an apostrophe, but Posix file names can't have apostrophes.
561# Zone NAME GMTOFF RULES FORMAT [UNTIL]
562Zone America/St_Johns -3:30:52 - LMT 1884
563 -3:31 StJohns N%sT 1935 Mar 30
564 -3:30 StJohns N%sT
565
566
567# Labrador, New Brunswick, Nova Scotia, Prince Edward I
568
569# From Paul Eggert (1996-06-12):
570# Shanks writes that since 1970 most of this region has been like Halifax.
571# Many locales did not observe peacetime DST until 1972;
572# Glace Bay, NS is the largest that we know of.
573# Shanks also writes that Liverpool, NS was the only town in Canada to observe
--- 44 unchanged lines hidden (view full) ---
618Zone America/Halifax -4:14:24 - LMT 1902 Jun 15
619 -4:00 Halifax A%sT
620Zone America/Glace_Bay -3:59:48 - LMT 1902 Jun 15
621 -4:00 Canada A%sT 1953
622 -4:00 Halifax A%sT 1954
623 -4:00 - AST 1972
624 -4:00 Halifax A%sT
625
626
627# Ontario, Quebec
628
629# From Paul Eggert (1996-06-12):
630# Shanks writes that since 1970 most of this region has been like Montreal.
631# Thunder Bay skipped DST in 1973.
632# Many smaller locales did not observe peacetime DST until 1974;
633# Nipigon (EST) and Rainy River (CST) are the largest that we know of.
--- 36 unchanged lines hidden (view full) ---
670 -5:00 Mont E%sT 1973
671 -5:00 - EST 1974
672 -5:00 Canada E%sT
673Zone America/Nipigon -5:53:04 - LMT 1895
674 -5:00 Canada E%sT
675Zone America/Rainy_River -6:17:56 - LMT 1895
676 -6:00 Canada C%sT
677
678
679# Manitoba
680
681# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
682Rule Winn 1916 only - Apr 23 0:00 1:00 D
683Rule Winn 1916 only - Sep 17 0:00 0 S
684Rule Winn 1918 only - Apr 14 2:00 1:00 D
685Rule Winn 1918 only - Oct 31 2:00 0 S
686Rule Winn 1937 only - May 16 2:00 1:00 D
687Rule Winn 1937 only - Sep 26 2:00 0 S
688Rule Winn 1942 only - Feb 9 2:00 1:00 D
--- 12 unchanged lines hidden (view full) ---
701Rule Winn 1963 only - Sep 22 2:00 0 S
702Rule Winn 1966 1986 - Apr lastSun 2:00 1:00 D
703Rule Winn 1966 max - Oct lastSun 2:00 0 S
704Rule Winn 1987 max - Apr Sun>=1 2:00 1:00 D
705# Zone NAME GMTOFF RULES FORMAT [UNTIL]
706Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16
707 -6:00 Winn C%sT
708
709
710# Saskatchewan
711
712# From Paul Eggert (1996-06-12):
713# Shanks writes that since 1970 most of this region has been like Regina.
714# Some western towns (e.g. Swift Current) switched from MST/MDT to CST in 1972.
715# Other western towns (e.g. Lloydminster) are like Edmonton.
716
717# From W. Jones <jones@skdad.usask.ca> (1992-11-06):
718# The. . .below is based on information I got from our law library, the
719# provincial archives, and the provincial Community Services department.
720# A precise history would require digging through newspaper archives, and
721# since you didn't say what you wanted, I didn't bother.
722#
723# Saskatchewan is split by a time zone meridian (105W) and over the years
724# the boundary became pretty ragged as communities near it reevaluated
725# their affiliations in one direction or the other. In 1965 a provincial
--- 41 unchanged lines hidden (view full) ---
767 -7:00 Regina M%sT 1960 Apr lastSun 2:00
768 -6:00 - CST
769Zone America/Swift_Current -7:11:20 - LMT 1905 Sep
770 -7:00 Canada M%sT 1946 Apr lastSun 2:00
771 -7:00 Regina M%sT 1950
772 -7:00 Swift M%sT 1972 Apr lastSun 2:00
773 -6:00 - CST
774
775
776# Alberta
777
778# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
779Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D
780Rule Edm 1918 only - Oct 31 2:00 0 S
781Rule Edm 1919 only - May 27 2:00 0 S
782Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D
--- 9 unchanged lines hidden (view full) ---
792Rule Edm 1969 only - Oct lastSun 2:00 0 S
793Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D
794Rule Edm 1972 max - Oct lastSun 2:00 0 S
795Rule Edm 1987 max - Apr Sun>=1 2:00 1:00 D
796# Zone NAME GMTOFF RULES FORMAT [UNTIL]
797Zone America/Edmonton -7:33:52 - LMT 1906 Sep
798 -7:00 Edm M%sT
799
800
801# British Columbia
802
803# From Paul Eggert (1996-06-12):
804# Shanks writes that since 1970 most of this region has been like Vancouver.
805# Dawswon Creek uses MST. Much of east BC is like Edmonton.
806
807# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
--- 9 unchanged lines hidden (view full) ---
817# Zone NAME GMTOFF RULES FORMAT [UNTIL]
818Zone America/Vancouver -8:12:28 - LMT 1884
819 -8:00 Vanc P%sT
820Zone America/Dawson_Creek -8:00:56 - LMT 1884
821 -8:00 Canada P%sT 1947
822 -8:00 Vanc P%sT 1972 Aug 30 2:00
823 -7:00 - MST
824
825
826# Northwest Territories, Yukon
827
828# From Paul Eggert (1996-06-12):
829# Dawson switched to PST in 1973. Inuvik switched to MST in 1979.
830# Shanks's table for Watson Lake is corrupted, so we have no data there.
831
832# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
833Rule NT_YK 1918 only - Apr 14 2:00 1:00 D
834Rule NT_YK 1918 only - Oct 27 2:00 0 S
835Rule NT_YK 1919 only - May 25 2:00 1:00 D
836Rule NT_YK 1919 only - Nov 1 0:00 0 S
837Rule NT_YK 1942 only - Feb 9 2:00 1:00 D
838Rule NT_YK 1945 only - Sep 30 2:00 0 S
839Rule NT_YK 1965 only - Apr lastSun 0:00 2:00 DD
840Rule NT_YK 1965 only - Oct lastSun 2:00 0 S
841Rule NT_YK 1980 1986 - Apr lastSun 2:00 1:00 D
842Rule NT_YK 1980 max - Oct lastSun 2:00 0 S
843Rule NT_YK 1987 max - Apr Sun>=1 2:00 1:00 D
844# Zone NAME GMTOFF RULES FORMAT [UNTIL]
845Zone America/Pangnirtung -4:22:56 - LMT 1884
846 -4:00 NT_YK A%sT
--- 8 unchanged lines hidden (view full) ---
855 -7:00 NT_YK M%sT
856Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20
857 -9:00 NT_YK Y%sT 1966 Jul 1 2:00
858 -8:00 NT_YK P%sT
859Zone America/Dawson -9:17:40 - LMT 1900 Aug 20
860 -9:00 NT_YK Y%sT 1973 Oct lastSun 2:00
861 -8:00 NT_YK P%sT
862
863
864###############################################################################
865
866# Mexico
867
868# From Guy Harris:
869# Rules are from the Official Airline Guide, Worldwide Edition, for 1987.
870# Rules prior to 1987 are unknown.
871# The comments in the OAG say "Only Ensenada, Mexicale, San Felipe and Tijuana
872# observe DST." This is presumably Baja California Norte, above 28th parallel,
873# as listed there; [there is also] "Baja California Sur and N. Pacific
874# Coast (States of Sinaloa and Sonora)."
875
876# From Bob Devine (1988-01-28):
877# The Federal District (where Mexico City is) has observed [DST] several
878# times but not recently.
879#
880# I don't where to drawn the line in the North Baja area. 28th latitude
881# sounds good -- but it may be higher (how far [d]o radio stations from
882# San Diego affect culture?).
883#
884# The dates of DST probably go back to 1981. The rules are the same as
885# US's. This is going to be a headache for US presidential electi[o]n years!
886
887# From Arthur David Olson (1988-02-13)
888# Since the 1981 starting date is only "probable," we'll keep the 1987
889# starting date below.
890
891# From U. S. Naval Observatory (1989-01-19):
892# MEXICO BAJA CAL N 7 H BEHIND UTC BAJA CALIFORNIA SUR AND
893# MEXICO BAJA CAL N N. PACIFIC COAST (STATES
894# MEXICO BAJA CAL N OF SINALOA AND SONORA)
895# MEXICO BAJA CAL N 8 H BEHIND UTC ABOVE 28TH PARALLAL APR 3
896# MEXICO BAJA CAL N - OCT 29
897# MEXICO BAJA CAL N 7 H BEHIND UTC ABOVE 28TH PARALLAL APR 3
898# MEXICO BAJA CAL N - 0CT 29
899# MEXICO 6 H BEHIND UTC STATES OF DURANGO,
900# MEXICO COAHUILA, NUEVO LEON,
901# MEXICO TAMAULIPAS
902# MEXICO 5 H BEHIND UTC STATES OF DURANGO,
903# MEXICO COAHUILA, NUEVO LEON,
904# MEXICO TAMAULIPAS APR 3 - OCT 29
905# MEXICO 6 H BEHIND UTC GENERAL MEXICO, STATES OF
906# MEXICO CAMPECHE, QUINTANA ROO AND
907# MEXICO YUCATAN
908
909# From Arthur David Olson (1989-01-21):
910# April 3 fell on a Sunday in 1988; October 29 fell on a Sunday in 1989. Ahem.
911# USNO claims there should be four Mexican zones rather than three:
912# a zone that's GMT-8 with DST; a zone that's always GMT-7;
913# a zone that's GMT-6 with DST; and a zone that's always GMT-6.
914
915# From Paul Eggert <eggert@twinsun.com> (1993-11-18):
916# Shanks also says there are four zones, but disagrees about the fourth.
917# Instead of GMT-6 with DST, he says there's GMT-8 without DST.
--- 50 unchanged lines hidden (view full) ---
968# Zone NAME GMTOFF RULES FORMAT [UNTIL]
969Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 0:23:24
970 -7:00 - MST 1927 Jun 10 23:00
971 -6:00 - CST 1930 Nov 15
972 -7:00 - MST 1931 May 1 23:00
973 -6:00 - CST 1931 Oct
974 -7:00 - MST 1932 Mar 30 23:00
975 -6:00 Mexico C%sT
976Zone America/Mazatlan -7:05:40 - LMT 1921 Dec 31 23:54:20
977 -7:00 - MST 1927 Jun 10 23:00
978 -6:00 - CST 1930 Nov 15
979 -7:00 - MST 1931 May 1 23:00
980 -6:00 - CST 1931 Oct
981 -7:00 - MST 1932 Mar 30 23:00
982 -6:00 - CST 1942 Apr
983 -7:00 - MST 1949 Jan 14
984 -8:00 - PST 1970
985 -7:00 Mexico M%sT
986Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 0:11:56
987 -8:00 - PST 1927 Jun 10 23:00
988 -7:00 - MST 1930 Nov 16
989 -8:00 - PST 1942 Apr
990 -7:00 - MST 1949 Jan 14
991 -8:00 BajaN P%sT 1967 Apr lastSun 2:00
992 -8:00 US P%sT 1996
993 -8:00 Mexico P%sT
994Zone America/Ensenada -7:46:28 - LMT 1922 Jan 1 0:13:32
995 -8:00 - PST 1927 Jun 10 23:00
996 -7:00 - MST 1930 Nov 16
997 -8:00 - PST 1942 Apr
998 -7:00 - MST 1949 Jan 14
999 -8:00 - PST 1996
1000 -8:00 Mexico P%sT
1001#
1002# Revillagigedo Is
1003# no information
1004
1005###############################################################################
1006
1007# Anguilla
1008# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1009Zone America/Anguilla -4:12:16 - LMT 1912 Mar 2
1010 -4:00 - AST
1011
1012# Antigua and Barbuda
1013# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1014Zone America/Antigua -4:07:12 - LMT 1912 Mar 2
1015 -5:00 - EST 1951
1016 -4:00 - AST
1017
1018# Bahamas
1019# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1020Rule Bahamas 1964 max - Oct lastSun 2:00 0 S
1021Rule Bahamas 1964 1986 - Apr lastSun 2:00 1:00 D
1022Rule Bahamas 1987 max - Apr Sun>=1 2:00 1:00 D
1023# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1024Zone America/Nassau -5:09:24 - LMT 1912 Mar 2
1025 -5:00 Bahamas E%sT
1026
1027# Barbados
1028# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1029Rule Barb 1977 only - Jun 12 2:00 1:00 D
1030Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S
1031Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D
1032Rule Barb 1979 only - Sep 30 2:00 0 S
1033Rule Barb 1980 only - Sep 25 2:00 0 S
1034# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1035Zone America/Barbados -3:58:28 - LMT 1924 # Bridgetown
1036 -3:58 - BMT 1932 # Bridgetown Mean Time
1037 -4:00 Barb A%sT
1038
1039# Belize
1040# Whitman entirely disagrees with Shanks; go with Shanks.
1041# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1042Rule Belize 1918 1942 - Oct Sun>=2 0:00 0:30 HD
1043Rule Belize 1919 1943 - Feb Sun>=9 0:00 0 S
1044Rule Belize 1973 only - Dec 5 0:00 1:00 D
1045Rule Belize 1974 only - Feb 9 0:00 0 S
1046Rule Belize 1982 only - Dec 18 0:00 1:00 D
1047Rule Belize 1983 only - Feb 12 0:00 0 S
1048# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1049Zone America/Belize -5:52:48 - LMT 1912 Apr
1050 -6:00 Belize C%sT
1051
1052# Bermuda
1053# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1054Zone Atlantic/Bermuda -4:19:04 - LMT 1930 Jan 1 2:00 # Hamilton
1055 -4:00 - AST 1974 Apr 28 2:00
1056 -4:00 Bahamas A%sT
1057
1058# Cayman Is
1059# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1060Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown
1061 -5:07 - KMT 1912 Feb # Kingston Mean Time
1062 -5:00 - EST
1063
1064# Clipperton
1065# uninhabited
1066
1067# Costa Rica
1068# Shanks gives some very odd dates for 1991, and stops there.
1069# For now, we won't guess further.
1070# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1071Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D
1072Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S
1073Rule CR 1991 only - Jan 19 0:00 1:00 D
1074Rule CR 1991 only - Jul 1 0:00 0 S
1075# There are too many San Joses elsewhere, so we'll use `Costa Rica'.
1076# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1077Zone America/Costa_Rica -5:36:20 - LMT 1890 # San Jose
1078 -5:36 - SJMT 1921 Jan 15 # San Jose Mean Time
1079 -6:00 CR C%sT
1080# Coco
1081# no information; probably like America/Costa_Rica
1082
1083# Cuba
1084
1085# From Bob Devine (1988-01-28):
1086# . . .DST is from 2nd Sunday in May to 2nd Sunday in October since 1981.
1087# Change at midnight. In 1979 & 1980, started at 3rd Sunday in March
1088# (I think).
1089
1090# From U. S. Naval Observatory (1989-01-19):
1091# CUBA 5 H BEHIND UTC
1092# CUBA 4 H BEHIND UTC MAR 20 - OCT 8
1093
1094# From Shanks (1991):
1095# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1096Rule Cuba 1928 only - Jun 10 0:00 1:00 D
1097Rule Cuba 1928 only - Oct 10 0:00 0 S
1098Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D
--- 20 unchanged lines hidden (view full) ---
1119Rule Cuba 1990 only - Apr 1 0:00 1:00 D
1120Rule Cuba 1991 max - Mar Sun>=14 0:00 1:00 D
1121
1122# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1123Zone America/Havana -5:29:28 - LMT 1890
1124 -5:30 - HMT 1925 Jul 19 12:00 # Havana MT
1125 -5:00 Cuba C%sT
1126
1127# Dominica
1128# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1129Zone America/Dominica -4:05:36 - LMT 1911 Jul 1 0:01 # Roseau
1130 -4:00 - AST
1131
1132# Dominican Republic
1133# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1134Rule DR 1966 only - Oct 30 0:00 1:00 D
1135Rule DR 1967 only - Feb 28 0:00 0 S
1136Rule DR 1969 1973 - Oct lastSun 0:00 0:30 HD
1137Rule DR 1970 only - Feb 21 0:00 0 S
1138Rule DR 1971 only - Jan 20 0:00 0 S
1139Rule DR 1972 1974 - Jan 21 0:00 0 S
1140# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1141Zone America/Santo_Domingo -4:39:36 - LMT 1890
1142 -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT
1143 -5:00 DR E%sT 1974 Oct 27
1144 -4:00 - AST
1145
1146# El Salvador
1147# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1148Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D
1149Rule Salv 1987 1988 - Sep lastSun 0:00 0 S
1150# There are too many San Salvadors elsewhere, so we'll use `El Salvador'.
1151# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1152Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador
1153 -6:00 Salv C%sT
1154
1155# Grenada
1156# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1157Zone America/Grenada -4:07:00 - LMT 1911 Jul # St George's
1158 -4:00 - AST
1159
1160# Guadeloupe
1161# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1162Zone America/Guadeloupe -4:06:08 - LMT 1911 Jun 8 # Pointe a Pitre
1163 -4:00 - AST
1164
1165# Guatemala
1166# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1167Rule Guat 1973 only - Nov 25 0:00 1:00 D
1168Rule Guat 1974 only - Feb 24 0:00 0 S
1169Rule Guat 1983 only - May 21 0:00 1:00 D
1170Rule Guat 1983 only - Sep 22 0:00 0 S
1171# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1172Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5
1173 -6:00 Guat C%sT
1174
1175# Haiti
1176# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1177Rule Haiti 1983 only - May 8 0:00 1:00 D
1178Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D
1179Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S
1180Rule Haiti 1988 max - Apr Sun>=1 2:00 1:00 D
1181Rule Haiti 1988 max - Oct lastSun 2:00 0 S
1182# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1183Zone America/Port-au-Prince -4:49:20 - LMT 1890
1184 -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT
1185 -5:00 Haiti E%sT
1186
1187# Honduras
1188# Shanks says 1921 Jan 1; go with Whitman's more precise Apr 1.
1189# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1190Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr
1191 -6:00 Salv C%sT
1192
1193# Jamaica
1194
1195# From Bob Devine (1988-01-28):
1196# Follows US rules.
1197
1198# From U. S. Naval Observatory (1989-01-19):
1199# JAMAICA 5 H BEHIND UTC
1200
1201# From Shanks (1991):
1202# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1203Zone America/Jamaica -5:07:12 - LMT 1890 # Kingston
1204 -5:07 - KMT 1912 Feb # Kingston Mean Time
1205 -5:00 - EST 1974 Jan 6 2:00
1206 -5:00 US E%sT
1207
1208# Martinique
1209# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1210Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France
1211 -4:04 - FFMT 1911 May # Fort-de-France MT
1212 -4:00 - AST 1980 Apr 6
1213 -4:00 1:00 ADT 1980 Sep 28
1214 -4:00 - AST
1215
1216# Montserrat
1217# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1218Zone America/Montserrat -4:08:52 - LMT 1911 Jul 1 0:01 # Plymouth
1219 -4:00 - AST
1220
1221# Nicaragua
1222# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1223Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D
1224Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S
1225# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1226Zone America/Managua -5:45:08 - LMT 1890
1227 -5:45 - MMT 1934 Jun 23 # Managua Mean Time
1228 -6:00 - CST 1973 May
1229 -5:00 - EST 1975 Feb 16
1230 -6:00 Nic C%sT
1231
1232# Panama
1233# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1234Zone America/Panama -5:18:08 - LMT 1890
1235 -5:20 - PMT 1908 Apr 22 # Panama Mean Time
1236 -5:00 - EST
1237
1238# Puerto Rico
1239# There are too many San Juans elsewhere, so we'll use `Puerto_Rico'.
1240# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1241Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan
1242 -4:00 - AST 1942 May 3
1243 -4:00 1:00 AWT 1945 Sep 30 2:00
1244 -4:00 - AST
1245
1246# St Kitts-Nevis
1247# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1248Zone America/St_Kitts -4:10:52 - LMT 1912 Mar 2 # Basseterre
1249 -4:00 - AST
1250
1251# St Lucia
1252# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1253Zone America/St_Lucia -4:04:00 - LMT 1890 # Castries
1254 -4:04 - CMT 1912 # Castries Mean Time
1255 -4:00 - AST
1256
1257# St Pierre and Miquelon
1258# There are too many St Pierres elsewhere, so we'll use `Miquelon'.
1259# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1260Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre
1261 -4:00 - AST 1980 May
1262 -3:00 Mont PM%sT # Pierre & Miquelon Time
1263
1264# St Vincent and the Grenadines
1265# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1266Zone America/St_Vincent -4:04:56 - LMT 1890 # Kingstown
1267 -4:05 - KMT 1912 # Kingstown Mean Time
1268 -4:00 - AST
1269
1270# Turks and Caicos
1271# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1272Zone America/Grand_Turk -4:44:32 - LMT 1890
1273 -5:07 - KMT 1912 Feb # Kingston Mean Time
1274 -5:00 - EST 1979 Apr 29 2:00
1275 -5:00 US E%sT
1276
1277# British Virgin Is
1278# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1279Zone America/Tortola -4:18:28 - LMT 1911 Jul # Road Town
1280 -4:00 - AST
1281
1282# Virgin Is
1283# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1284Zone America/St_Thomas -4:19:44 - LMT 1911 Jul # Charlotte Amalie
1285 -4:00 - AST
2# also includes Central America and the Caribbean
3
4# This data is by no means authoritative; if you think you know better,
5# go ahead and edit the file (and please send any changes to
6# tz@elsie.nci.nih.gov for general use in the future).
7
8# From Paul Eggert <eggert@twinsun.com> (1994-08-17):
9# A reliable and entertaining source about time zones is
10# Derek Howse, Greenwich time and the discovery of the longitude,
11# Oxford University Press (1980).
12
13###############################################################################
14
15# United States
16
--- 19 unchanged lines hidden (view full) ---
36# scheme I detect the bony, blue-fingered hand of Puritanism, eager
37# to push people into bed earlier, and get them up earlier, to make
38# them healthy, wealthy and wise in spite of themselves.
39#
40# -- Robertson Davies, The Diary of Samuel Marchbanks (1947), XIX, Sunday
41
42# From Arthur David Olson:
43# US Daylight Saving Time ended on the last Sunday of *October* in 1974.
44# See, for example, the front page of the Saturday, 1974-10-26
45# and Sunday, 1974-10-27 editions of the Washington Post.
46
47# From Arthur David Olson:
48# Before the Uniform Time Act of 1966 took effect in 1967, observance of
49# Daylight Saving Time in the US was by local option, except during wartime.
50
51# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
52Rule US 1918 1919 - Mar lastSun 2:00 1:00 W # War
53Rule US 1918 1919 - Oct lastSun 2:00 0 S
54Rule US 1942 only - Feb 9 2:00 1:00 W # War
55Rule US 1945 only - Sep 30 2:00 0 S
56Rule US 1967 max - Oct lastSun 2:00 0 S
57Rule US 1967 1973 - Apr lastSun 2:00 1:00 D
58Rule US 1974 only - Jan 6 2:00 1:00 D
59Rule US 1975 only - Feb 23 2:00 1:00 D
60Rule US 1976 1986 - Apr lastSun 2:00 1:00 D
61Rule US 1987 max - Apr Sun>=1 2:00 1:00 D
62
63# From Bob Devine (1988-01-28):
64# ...Alaska (and Hawaii) had the timezone names changed in 1967.
65# old new
66# Pacific Standard Time(PST) -same-
67# Yukon Standard Time(YST) -same-
68# Central Alaska S.T. (CAT) Alaska-Hawaii St[an]dard Time (AHST)
69# Nome Standard Time (NT) Bering Standard Time (BST)
70#
71# ...Alaska's timezone lines were redrawn in 1983 to give only 2 tz.
72# The YST zone now covers nearly all of the state, AHST just part
73# of the Aleutian islands. No DST.
74
75# From Paul Eggert (1995-12-19):
76# The tables below use `NST', not `NT', for Nome Standard Time.
77# I invented `CAWT' for Central Alaska War Time.
78
79# From U. S. Naval Observatory (1989-01-19):
80# USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON
81# USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30
82# USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON
83# USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30
84# USA MOUNTAIN 7 H BEHIND UTC DENVER
85# USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30
86# USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO
87# USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30
88# USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST)
89# USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT)
90# USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W
91# USA - " - 9 H BEHIND UTC APR 3 - OCT 30
92# USA HAWAII 10 H BEHIND UTC
93# USA BERING 11 H BEHIND UTC SAMOA, MIDWAY
94
95# From Arthur David Olson (1989-01-21):
96# The above dates are for 1988.
97# Note the "AKST" and "AKDT" abbreviations, the claim that there's
98# no DST in Samoa, and the claim that there is DST in Alaska and the
99# Aleutians.
100
101# From Arthur David Olson (1988-02-13):
102# Legal standard time zone names, from United States Code (1982 Edition and
103# Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names
104# up to 1967-04-01 (when most provisions of the Uniform Time Act of 1966
105# took effect), as explained in sections 263 and 261:
106# (none)
107# United States standard eastern time
108# United States standard mountain time
109# United States standard central time
110# United States standard Pacific time
111# (none)
112# United States standard Alaska time
113# (none)
114# Next, names from 1967-04-01 until 1983-11-30 (the date for
115# public law 98-181):
116# Atlantic standard time
117# eastern standard time
118# central standard time
119# mountain standard time
120# Pacific standard time
121# Yukon standard time
122# Alaska-Hawaii standard time
123# Bering standard time
124# And after 1983-11-30:
125# Atlantic standard time
126# eastern standard time
127# central standard time
128# mountain standard time
129# Pacific standard time
130# Alaska standard time
131# Hawaii-Aleutian standard time
132# Samoa standard time
--- 12 unchanged lines hidden (view full) ---
145Rule NYC 1955 1966 - Oct lastSun 2:00 0 S
146# Zone NAME GMTOFF RULES FORMAT [UNTIL]
147Zone America/New_York -4:56:02 - LMT 1883 Nov 18 12:00
148 -5:00 US E%sT 1920
149 -5:00 NYC E%sT 1942
150 -5:00 US E%sT 1946
151 -5:00 NYC E%sT 1967
152 -5:00 US E%sT
153
154# US Central time, represented by Chicago
155# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
156Rule Chicago 1920 only - Jun 13 2:00 1:00 D
157Rule Chicago 1920 1921 - Oct lastSun 2:00 0 S
158Rule Chicago 1921 only - Mar lastSun 2:00 1:00 D
159Rule Chicago 1922 1966 - Apr lastSun 2:00 1:00 D
160Rule Chicago 1922 1954 - Sep lastSun 2:00 0 S
161Rule Chicago 1955 1966 - Oct lastSun 2:00 0 S
162# Zone NAME GMTOFF RULES FORMAT [UNTIL]
163Zone America/Chicago -5:50:36 - LMT 1883 Nov 18 12:00
164 -6:00 US C%sT 1920
165 -6:00 Chicago C%sT 1936 Mar 1 2:00
166 -5:00 - EST 1936 Nov 15 2:00
167 -6:00 Chicago C%sT 1942
168 -6:00 US C%sT 1946
169 -6:00 Chicago C%sT 1967
170 -6:00 US C%sT
171
172# US Mountain time, represented by Denver
173# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
174Rule Denver 1920 1921 - Mar lastSun 2:00 1:00 D
175Rule Denver 1920 only - Oct lastSun 2:00 0 S
176Rule Denver 1921 only - May 22 2:00 0 S
177Rule Denver 1965 1966 - Apr lastSun 2:00 1:00 D
178Rule Denver 1965 1966 - Oct lastSun 2:00 0 S
179# Zone NAME GMTOFF RULES FORMAT [UNTIL]
180Zone America/Denver -6:59:56 - LMT 1883 Nov 18 12:00
181 -7:00 US M%sT 1920
182 -7:00 Denver M%sT 1942
183 -7:00 US M%sT 1946
184 -7:00 Denver M%sT 1967
185 -7:00 US M%sT
186
187# US Pacific time, represented by Los Angeles
188# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
189Rule CA 1948 only - Mar 14 2:00 1:00 D
190Rule CA 1949 only - Jan 1 2:00 0 S
191Rule CA 1950 1966 - Apr lastSun 2:00 1:00 D
192Rule CA 1950 1961 - Sep lastSun 2:00 0 S
193Rule CA 1962 1966 - Oct lastSun 2:00 0 S
194# Zone NAME GMTOFF RULES FORMAT [UNTIL]
195Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 12:00
196 -8:00 US P%sT 1946
197 -8:00 CA P%sT 1967
198 -8:00 US P%sT
199
200# Alaska
201# AK%sT is the modern abbreviation for -9:00 per USNO.
202#
203# From Paul Eggert (1995-12-19):
204# Howse writes that Alaska switched from the Julian to the Gregorian calendar,
205# and from east-of-GMT to west-of-GMT days, when the US bought it from Russia.
206# This was on 1867-10-18. We omit this transition, since we can't represent
207# changes from Julian to Gregorian.
208#
209# Zone NAME GMTOFF RULES FORMAT [UNTIL]
210Zone America/Juneau -8:57:41 - LMT 1900 Aug 20 12:00
211 -8:00 - PST 1942
212 -8:00 US P%sT 1946
213 -8:00 - PST 1969
214 -8:00 US P%sT 1983 Oct 30 2:00
215 -9:00 US AK%sT
--- 24 unchanged lines hidden (view full) ---
240 -11:00 - BST 1969
241 -11:00 US B%sT 1983 Oct 30 2:00
242 -10:00 US HA%sT
243# Shanks writes that part of southwest Alaska (e.g. Aniak)
244# switched from -11:00 to -10:00 on 1968-09-22 at 02:00,
245# and another part (e.g. Akiak) made the same switch five weeks later.
246# These switches don't quite make our 1970 cutoff.
247
248# Hawaii
249#
250# From Arthur David Olson:
251# And then there's Hawaii.
252# DST was observed for one day in 1933;
253# standard time was changed by half an hour in 1947;
254# it's always standard as of 1986.
255#
--- 6 unchanged lines hidden (view full) ---
262 -10:30 US H%sT 1947 Jun 8 2:00
263 -10:00 - HST
264
265Zone Pacific/Midway -11:49:28 - LMT 1901
266 -11:00 - NST 1967 Apr # N=Nome
267 -11:00 - BST 1983 Nov 30 # B=Bering
268 -11:00 - SST # S=Samoa
269
270# Now we turn to US areas that have diverged from the consensus since 1970.
271
272# Arizona mostly uses MST.
273Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 12:00
274 -7:00 US M%sT 1944 Jan 1 00:01
275 -7:00 - MST 1944 Mar 17 00:01
276 -7:00 US M%sT 1944 Oct 1 00:01
277 -7:00 - MST 1967
278 -7:00 US M%sT 1968
279 -7:00 - MST
280# From Arthur David Olson (1988-02-13):
281# A writer from the Inter Tribal Council of Arizona, Inc.,
282# notes in private correspondence dated 12/28/87 that "Presently, only the
283# Navajo Nation participates in the Daylight Saving Time policy, due to its
284# large size and location in three states." (The "only" means that other
285# tribal nations don't use DST.)
286
287Link America/Denver America/Shiprock
288
289# Southern Idaho and eastern Oregon switched four weeks late in 1974.
290# Zone NAME GMTOFF RULES FORMAT [UNTIL]
291Zone America/Boise -7:44:49 - LMT 1883 Nov 18 12:00
292 -8:00 US P%sT 1923 May 13 2:00
293 -7:00 US M%sT 1974
294 -7:00 - MST 1974 Feb 3 2:00
295 -7:00 US M%sT
296
297# Indiana
298#
299# From Paul Eggert (1995-12-19):
300# Indiana generally observes either EST all year, or CST/CDT,
301# but areas near Cincinnati and Louisville use those cities' timekeeping
302# and in 1969 and 1970 the whole state observed daylight time;
303# and there are other exceptions as noted below.
304# Shanks partitions Indiana into 345 regions, each with its own time history,
--- 21 unchanged lines hidden (view full) ---
326 -6:00 US C%sT 1946
327 -6:00 Indianapolis C%sT 1955 Apr 24 2:00
328 -5:00 - EST 1957 Sep 29 2:00
329 -6:00 - CST 1958 Apr 27 2:00
330 -5:00 - EST 1969
331 -5:00 US E%sT 1971
332 -5:00 - EST
333Link America/Indianapolis America/Indiana/Indianapolis
334#
335# Part of Crawford County, Indiana, last observed DST in 1975,
336# and left its clocks alone in 1974.
337# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
338Rule Marengo 1951 only - Apr lastSun 2:00 1:00 D
339Rule Marengo 1951 only - Sep lastSun 2:00 0 S
340Rule Marengo 1954 1960 - Apr lastSun 2:00 1:00 D
341Rule Marengo 1954 1960 - Sep lastSun 2:00 0 S
342# Zone NAME GMTOFF RULES FORMAT [UNTIL]
343Zone America/Indiana/Marengo -5:45:23 - LMT 1883 Nov 18 12:00
344 -6:00 US C%sT 1951
345 -6:00 Marengo C%sT 1961 Apr 30 2:00
346 -5:00 - EST 1969
347 -5:00 US E%sT 1974 Jan 6 2:00
348 -6:00 1:00 CDT 1974 Oct 27 2:00
349 -5:00 US E%sT 1976
350 -5:00 - EST
351#
352# Starke County, Indiana
353# From Arthur David Olson (1991-10-28):
354# An article on page A3 of the Sunday, 1991-10-27 Washington Post
355# notes that Starke County switched from Central time to Eastern time as of
356# 1991-10-27.
357# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
358Rule Starke 1947 1961 - Apr lastSun 2:00 1:00 D
359Rule Starke 1947 1954 - Sep lastSun 2:00 0 S
360Rule Starke 1955 1956 - Oct lastSun 2:00 0 S
361Rule Starke 1957 1958 - Sep lastSun 2:00 0 S
362Rule Starke 1959 1961 - Oct lastSun 2:00 0 S
363# Zone NAME GMTOFF RULES FORMAT [UNTIL]
364Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 12:00
365 -6:00 US C%sT 1947
366 -6:00 Starke C%sT 1962 Apr 29 2:00
367 -5:00 - EST 1963 Oct 27 2:00
368 -6:00 US C%sT 1991 Oct 27 2:00
369 -5:00 - EST
370#
371# Switzerland County, Indiana, last observed DST in 1972.
372# Zone NAME GMTOFF RULES FORMAT [UNTIL]
373Zone America/Indiana/Vevay -5:40:16 - LMT 1883 Nov 18 12:00
374 -6:00 US C%sT 1954 Apr 25 2:00
375 -5:00 - EST 1969
376 -5:00 US E%sT 1973
377 -5:00 - EST
378
379# Part of Kentucky left its clocks alone in 1974.
380# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
381Rule Louisville 1921 only - May 1 2:00 1:00 D
382Rule Louisville 1921 only - Sep 1 2:00 0 S
383Rule Louisville 1941 1961 - Apr lastSun 2:00 1:00 D
384Rule Louisville 1941 only - Sep lastSun 2:00 0 S
385Rule Louisville 1946 only - Jun 2 2:00 0 S
386Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S
--- 4 unchanged lines hidden (view full) ---
391 -6:00 Louisville C%sT 1942
392 -6:00 US C%sT 1946
393 -6:00 Louisville C%sT 1961 Jul 23 2:00
394 -5:00 - EST 1968
395 -5:00 US E%sT 1974 Jan 6 2:00
396 -6:00 1:00 CDT 1974 Oct 27 2:00
397 -5:00 US E%sT
398
399# Michigan
400#
401# From Bob Devine (1988-01-28):
402# Michigan didn't observe DST from 1968 to 1973.
403#
404# From Paul Eggert (1995-12-19):
405# Shanks writes that Michigan started using standard time on 1885 Sep 18,
406# but Howse (p 126) writes that Detroit kept
407#
408# local time until 1900 when the City Council decreed that clocks should
409# be put back twenty-eight minutes to Central Standard Time. Half the
--- 15 unchanged lines hidden (view full) ---
425Zone America/Detroit -5:32:11 - LMT 1905
426 -6:00 - CST 1915 May 15 2:00
427 -5:00 - EST 1942
428 -5:00 US E%sT 1946
429 -5:00 Detroit E%sT 1973
430 -5:00 US E%sT 1975
431 -5:00 - EST 1975 Apr 27 2:00
432 -5:00 US E%sT
433#
434# The Michigan border with Wisconsin switched from EST to CST/CDT in 1973.
435# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
436Rule Menominee 1946 only - Apr lastSun 2:00 1:00 D
437Rule Menominee 1946 only - Sep lastSun 2:00 0 S
438Rule Menominee 1966 only - Apr lastSun 2:00 1:00 D
439Rule Menominee 1966 only - Oct lastSun 2:00 0 S
440# Zone NAME GMTOFF RULES FORMAT [UNTIL]
441Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00
442 -6:00 US C%sT 1946
443 -6:00 Menominee C%sT 1969 Apr 27 2:00
444 -5:00 - EST 1973 Apr 29 2:00
445 -6:00 US C%sT
446
447# Navassa
448# uninhabited
449
450
451# Old names, for S5 users
452
453# Link LINK-FROM LINK-TO
454Link America/New_York EST5EDT
455Link America/Chicago CST6CDT
456Link America/Denver MST7MDT
457Link America/Los_Angeles PST8PDT
458Link America/Indianapolis EST
459Link America/Phoenix MST
460Link Pacific/Honolulu HST
461
462################################################################################
463
464
465# From Paul Eggert <eggert@twinsun.com> (1993-11-18):
466# A good source for time zone historical data outside the US is
467# Thomas G. Shanks, The International Atlas (3rd edition),
468# San Diego: ACS Publications, Inc. (1991).
469# Except where otherwise noted, it is the source for the data below.
470#
471# Another source occasionally used is Edward W. Whitman, World Time Differences,
472# Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated), which
473# I found in the UCLA library.
474#
475# See the `europe' file for Greenland.
476#
477# See the `africa' file for time zone naming and abbreviation conventions.
478
479# Canada
480
481# From Alain LaBont<e'> <ALB@immedia.ca> (1994-11-14):
482# I post here the time zone abbreviations standardized in Canada
483# for both English and French in the CAN/CSA-Z234.4-89 standard....
484#
485# UTC Standard time Daylight savings time
--- 72 unchanged lines hidden (view full) ---
558Rule StJohns 1988 only - Apr Sun>=1 2:00 2:00 DD
559Rule StJohns 1989 max - Apr Sun>=1 2:00 1:00 D
560# St John's has an apostrophe, but Posix file names can't have apostrophes.
561# Zone NAME GMTOFF RULES FORMAT [UNTIL]
562Zone America/St_Johns -3:30:52 - LMT 1884
563 -3:31 StJohns N%sT 1935 Mar 30
564 -3:30 StJohns N%sT
565
566
567# Labrador, New Brunswick, Nova Scotia, Prince Edward I
568
569# From Paul Eggert (1996-06-12):
570# Shanks writes that since 1970 most of this region has been like Halifax.
571# Many locales did not observe peacetime DST until 1972;
572# Glace Bay, NS is the largest that we know of.
573# Shanks also writes that Liverpool, NS was the only town in Canada to observe
--- 44 unchanged lines hidden (view full) ---
618Zone America/Halifax -4:14:24 - LMT 1902 Jun 15
619 -4:00 Halifax A%sT
620Zone America/Glace_Bay -3:59:48 - LMT 1902 Jun 15
621 -4:00 Canada A%sT 1953
622 -4:00 Halifax A%sT 1954
623 -4:00 - AST 1972
624 -4:00 Halifax A%sT
625
626
627# Ontario, Quebec
628
629# From Paul Eggert (1996-06-12):
630# Shanks writes that since 1970 most of this region has been like Montreal.
631# Thunder Bay skipped DST in 1973.
632# Many smaller locales did not observe peacetime DST until 1974;
633# Nipigon (EST) and Rainy River (CST) are the largest that we know of.
--- 36 unchanged lines hidden (view full) ---
670 -5:00 Mont E%sT 1973
671 -5:00 - EST 1974
672 -5:00 Canada E%sT
673Zone America/Nipigon -5:53:04 - LMT 1895
674 -5:00 Canada E%sT
675Zone America/Rainy_River -6:17:56 - LMT 1895
676 -6:00 Canada C%sT
677
678
679# Manitoba
680
681# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
682Rule Winn 1916 only - Apr 23 0:00 1:00 D
683Rule Winn 1916 only - Sep 17 0:00 0 S
684Rule Winn 1918 only - Apr 14 2:00 1:00 D
685Rule Winn 1918 only - Oct 31 2:00 0 S
686Rule Winn 1937 only - May 16 2:00 1:00 D
687Rule Winn 1937 only - Sep 26 2:00 0 S
688Rule Winn 1942 only - Feb 9 2:00 1:00 D
--- 12 unchanged lines hidden (view full) ---
701Rule Winn 1963 only - Sep 22 2:00 0 S
702Rule Winn 1966 1986 - Apr lastSun 2:00 1:00 D
703Rule Winn 1966 max - Oct lastSun 2:00 0 S
704Rule Winn 1987 max - Apr Sun>=1 2:00 1:00 D
705# Zone NAME GMTOFF RULES FORMAT [UNTIL]
706Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16
707 -6:00 Winn C%sT
708
709
710# Saskatchewan
711
712# From Paul Eggert (1996-06-12):
713# Shanks writes that since 1970 most of this region has been like Regina.
714# Some western towns (e.g. Swift Current) switched from MST/MDT to CST in 1972.
715# Other western towns (e.g. Lloydminster) are like Edmonton.
716
717# From W. Jones <jones@skdad.usask.ca> (1992-11-06):
718# The. . .below is based on information I got from our law library, the
719# provincial archives, and the provincial Community Services department.
720# A precise history would require digging through newspaper archives, and
721# since you didn't say what you wanted, I didn't bother.
722#
723# Saskatchewan is split by a time zone meridian (105W) and over the years
724# the boundary became pretty ragged as communities near it reevaluated
725# their affiliations in one direction or the other. In 1965 a provincial
--- 41 unchanged lines hidden (view full) ---
767 -7:00 Regina M%sT 1960 Apr lastSun 2:00
768 -6:00 - CST
769Zone America/Swift_Current -7:11:20 - LMT 1905 Sep
770 -7:00 Canada M%sT 1946 Apr lastSun 2:00
771 -7:00 Regina M%sT 1950
772 -7:00 Swift M%sT 1972 Apr lastSun 2:00
773 -6:00 - CST
774
775
776# Alberta
777
778# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
779Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D
780Rule Edm 1918 only - Oct 31 2:00 0 S
781Rule Edm 1919 only - May 27 2:00 0 S
782Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D
--- 9 unchanged lines hidden (view full) ---
792Rule Edm 1969 only - Oct lastSun 2:00 0 S
793Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D
794Rule Edm 1972 max - Oct lastSun 2:00 0 S
795Rule Edm 1987 max - Apr Sun>=1 2:00 1:00 D
796# Zone NAME GMTOFF RULES FORMAT [UNTIL]
797Zone America/Edmonton -7:33:52 - LMT 1906 Sep
798 -7:00 Edm M%sT
799
800
801# British Columbia
802
803# From Paul Eggert (1996-06-12):
804# Shanks writes that since 1970 most of this region has been like Vancouver.
805# Dawswon Creek uses MST. Much of east BC is like Edmonton.
806
807# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
--- 9 unchanged lines hidden (view full) ---
817# Zone NAME GMTOFF RULES FORMAT [UNTIL]
818Zone America/Vancouver -8:12:28 - LMT 1884
819 -8:00 Vanc P%sT
820Zone America/Dawson_Creek -8:00:56 - LMT 1884
821 -8:00 Canada P%sT 1947
822 -8:00 Vanc P%sT 1972 Aug 30 2:00
823 -7:00 - MST
824
825
826# Northwest Territories, Yukon
827
828# From Paul Eggert (1996-06-12):
829# Dawson switched to PST in 1973. Inuvik switched to MST in 1979.
830# Shanks's table for Watson Lake is corrupted, so we have no data there.
831
832# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
833Rule NT_YK 1918 only - Apr 14 2:00 1:00 D
834Rule NT_YK 1918 only - Oct 27 2:00 0 S
835Rule NT_YK 1919 only - May 25 2:00 1:00 D
836Rule NT_YK 1919 only - Nov 1 0:00 0 S
837Rule NT_YK 1942 only - Feb 9 2:00 1:00 D
838Rule NT_YK 1945 only - Sep 30 2:00 0 S
839Rule NT_YK 1965 only - Apr lastSun 0:00 2:00 DD
840Rule NT_YK 1965 only - Oct lastSun 2:00 0 S
841Rule NT_YK 1980 1986 - Apr lastSun 2:00 1:00 D
842Rule NT_YK 1980 max - Oct lastSun 2:00 0 S
843Rule NT_YK 1987 max - Apr Sun>=1 2:00 1:00 D
844# Zone NAME GMTOFF RULES FORMAT [UNTIL]
845Zone America/Pangnirtung -4:22:56 - LMT 1884
846 -4:00 NT_YK A%sT
--- 8 unchanged lines hidden (view full) ---
855 -7:00 NT_YK M%sT
856Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20
857 -9:00 NT_YK Y%sT 1966 Jul 1 2:00
858 -8:00 NT_YK P%sT
859Zone America/Dawson -9:17:40 - LMT 1900 Aug 20
860 -9:00 NT_YK Y%sT 1973 Oct lastSun 2:00
861 -8:00 NT_YK P%sT
862
863
864###############################################################################
865
866# Mexico
867
868# From Guy Harris:
869# Rules are from the Official Airline Guide, Worldwide Edition, for 1987.
870# Rules prior to 1987 are unknown.
871# The comments in the OAG say "Only Ensenada, Mexicale, San Felipe and Tijuana
872# observe DST." This is presumably Baja California Norte, above 28th parallel,
873# as listed there; [there is also] "Baja California Sur and N. Pacific
874# Coast (States of Sinaloa and Sonora)."
875
876# From Bob Devine (1988-01-28):
877# The Federal District (where Mexico City is) has observed [DST] several
878# times but not recently.
879#
880# I don't where to drawn the line in the North Baja area. 28th latitude
881# sounds good -- but it may be higher (how far [d]o radio stations from
882# San Diego affect culture?).
883#
884# The dates of DST probably go back to 1981. The rules are the same as
885# US's. This is going to be a headache for US presidential electi[o]n years!
886
887# From Arthur David Olson (1988-02-13)
888# Since the 1981 starting date is only "probable," we'll keep the 1987
889# starting date below.
890
891# From U. S. Naval Observatory (1989-01-19):
892# MEXICO BAJA CAL N 7 H BEHIND UTC BAJA CALIFORNIA SUR AND
893# MEXICO BAJA CAL N N. PACIFIC COAST (STATES
894# MEXICO BAJA CAL N OF SINALOA AND SONORA)
895# MEXICO BAJA CAL N 8 H BEHIND UTC ABOVE 28TH PARALLAL APR 3
896# MEXICO BAJA CAL N - OCT 29
897# MEXICO BAJA CAL N 7 H BEHIND UTC ABOVE 28TH PARALLAL APR 3
898# MEXICO BAJA CAL N - 0CT 29
899# MEXICO 6 H BEHIND UTC STATES OF DURANGO,
900# MEXICO COAHUILA, NUEVO LEON,
901# MEXICO TAMAULIPAS
902# MEXICO 5 H BEHIND UTC STATES OF DURANGO,
903# MEXICO COAHUILA, NUEVO LEON,
904# MEXICO TAMAULIPAS APR 3 - OCT 29
905# MEXICO 6 H BEHIND UTC GENERAL MEXICO, STATES OF
906# MEXICO CAMPECHE, QUINTANA ROO AND
907# MEXICO YUCATAN
908
909# From Arthur David Olson (1989-01-21):
910# April 3 fell on a Sunday in 1988; October 29 fell on a Sunday in 1989. Ahem.
911# USNO claims there should be four Mexican zones rather than three:
912# a zone that's GMT-8 with DST; a zone that's always GMT-7;
913# a zone that's GMT-6 with DST; and a zone that's always GMT-6.
914
915# From Paul Eggert <eggert@twinsun.com> (1993-11-18):
916# Shanks also says there are four zones, but disagrees about the fourth.
917# Instead of GMT-6 with DST, he says there's GMT-8 without DST.
--- 50 unchanged lines hidden (view full) ---
968# Zone NAME GMTOFF RULES FORMAT [UNTIL]
969Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 0:23:24
970 -7:00 - MST 1927 Jun 10 23:00
971 -6:00 - CST 1930 Nov 15
972 -7:00 - MST 1931 May 1 23:00
973 -6:00 - CST 1931 Oct
974 -7:00 - MST 1932 Mar 30 23:00
975 -6:00 Mexico C%sT
976Zone America/Mazatlan -7:05:40 - LMT 1921 Dec 31 23:54:20
977 -7:00 - MST 1927 Jun 10 23:00
978 -6:00 - CST 1930 Nov 15
979 -7:00 - MST 1931 May 1 23:00
980 -6:00 - CST 1931 Oct
981 -7:00 - MST 1932 Mar 30 23:00
982 -6:00 - CST 1942 Apr
983 -7:00 - MST 1949 Jan 14
984 -8:00 - PST 1970
985 -7:00 Mexico M%sT
986Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 0:11:56
987 -8:00 - PST 1927 Jun 10 23:00
988 -7:00 - MST 1930 Nov 16
989 -8:00 - PST 1942 Apr
990 -7:00 - MST 1949 Jan 14
991 -8:00 BajaN P%sT 1967 Apr lastSun 2:00
992 -8:00 US P%sT 1996
993 -8:00 Mexico P%sT
994Zone America/Ensenada -7:46:28 - LMT 1922 Jan 1 0:13:32
995 -8:00 - PST 1927 Jun 10 23:00
996 -7:00 - MST 1930 Nov 16
997 -8:00 - PST 1942 Apr
998 -7:00 - MST 1949 Jan 14
999 -8:00 - PST 1996
1000 -8:00 Mexico P%sT
1001#
1002# Revillagigedo Is
1003# no information
1004
1005###############################################################################
1006
1007# Anguilla
1008# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1009Zone America/Anguilla -4:12:16 - LMT 1912 Mar 2
1010 -4:00 - AST
1011
1012# Antigua and Barbuda
1013# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1014Zone America/Antigua -4:07:12 - LMT 1912 Mar 2
1015 -5:00 - EST 1951
1016 -4:00 - AST
1017
1018# Bahamas
1019# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1020Rule Bahamas 1964 max - Oct lastSun 2:00 0 S
1021Rule Bahamas 1964 1986 - Apr lastSun 2:00 1:00 D
1022Rule Bahamas 1987 max - Apr Sun>=1 2:00 1:00 D
1023# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1024Zone America/Nassau -5:09:24 - LMT 1912 Mar 2
1025 -5:00 Bahamas E%sT
1026
1027# Barbados
1028# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1029Rule Barb 1977 only - Jun 12 2:00 1:00 D
1030Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S
1031Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D
1032Rule Barb 1979 only - Sep 30 2:00 0 S
1033Rule Barb 1980 only - Sep 25 2:00 0 S
1034# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1035Zone America/Barbados -3:58:28 - LMT 1924 # Bridgetown
1036 -3:58 - BMT 1932 # Bridgetown Mean Time
1037 -4:00 Barb A%sT
1038
1039# Belize
1040# Whitman entirely disagrees with Shanks; go with Shanks.
1041# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1042Rule Belize 1918 1942 - Oct Sun>=2 0:00 0:30 HD
1043Rule Belize 1919 1943 - Feb Sun>=9 0:00 0 S
1044Rule Belize 1973 only - Dec 5 0:00 1:00 D
1045Rule Belize 1974 only - Feb 9 0:00 0 S
1046Rule Belize 1982 only - Dec 18 0:00 1:00 D
1047Rule Belize 1983 only - Feb 12 0:00 0 S
1048# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1049Zone America/Belize -5:52:48 - LMT 1912 Apr
1050 -6:00 Belize C%sT
1051
1052# Bermuda
1053# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1054Zone Atlantic/Bermuda -4:19:04 - LMT 1930 Jan 1 2:00 # Hamilton
1055 -4:00 - AST 1974 Apr 28 2:00
1056 -4:00 Bahamas A%sT
1057
1058# Cayman Is
1059# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1060Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown
1061 -5:07 - KMT 1912 Feb # Kingston Mean Time
1062 -5:00 - EST
1063
1064# Clipperton
1065# uninhabited
1066
1067# Costa Rica
1068# Shanks gives some very odd dates for 1991, and stops there.
1069# For now, we won't guess further.
1070# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1071Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D
1072Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S
1073Rule CR 1991 only - Jan 19 0:00 1:00 D
1074Rule CR 1991 only - Jul 1 0:00 0 S
1075# There are too many San Joses elsewhere, so we'll use `Costa Rica'.
1076# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1077Zone America/Costa_Rica -5:36:20 - LMT 1890 # San Jose
1078 -5:36 - SJMT 1921 Jan 15 # San Jose Mean Time
1079 -6:00 CR C%sT
1080# Coco
1081# no information; probably like America/Costa_Rica
1082
1083# Cuba
1084
1085# From Bob Devine (1988-01-28):
1086# . . .DST is from 2nd Sunday in May to 2nd Sunday in October since 1981.
1087# Change at midnight. In 1979 & 1980, started at 3rd Sunday in March
1088# (I think).
1089
1090# From U. S. Naval Observatory (1989-01-19):
1091# CUBA 5 H BEHIND UTC
1092# CUBA 4 H BEHIND UTC MAR 20 - OCT 8
1093
1094# From Shanks (1991):
1095# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1096Rule Cuba 1928 only - Jun 10 0:00 1:00 D
1097Rule Cuba 1928 only - Oct 10 0:00 0 S
1098Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D
--- 20 unchanged lines hidden (view full) ---
1119Rule Cuba 1990 only - Apr 1 0:00 1:00 D
1120Rule Cuba 1991 max - Mar Sun>=14 0:00 1:00 D
1121
1122# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1123Zone America/Havana -5:29:28 - LMT 1890
1124 -5:30 - HMT 1925 Jul 19 12:00 # Havana MT
1125 -5:00 Cuba C%sT
1126
1127# Dominica
1128# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1129Zone America/Dominica -4:05:36 - LMT 1911 Jul 1 0:01 # Roseau
1130 -4:00 - AST
1131
1132# Dominican Republic
1133# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1134Rule DR 1966 only - Oct 30 0:00 1:00 D
1135Rule DR 1967 only - Feb 28 0:00 0 S
1136Rule DR 1969 1973 - Oct lastSun 0:00 0:30 HD
1137Rule DR 1970 only - Feb 21 0:00 0 S
1138Rule DR 1971 only - Jan 20 0:00 0 S
1139Rule DR 1972 1974 - Jan 21 0:00 0 S
1140# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1141Zone America/Santo_Domingo -4:39:36 - LMT 1890
1142 -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT
1143 -5:00 DR E%sT 1974 Oct 27
1144 -4:00 - AST
1145
1146# El Salvador
1147# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1148Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D
1149Rule Salv 1987 1988 - Sep lastSun 0:00 0 S
1150# There are too many San Salvadors elsewhere, so we'll use `El Salvador'.
1151# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1152Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador
1153 -6:00 Salv C%sT
1154
1155# Grenada
1156# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1157Zone America/Grenada -4:07:00 - LMT 1911 Jul # St George's
1158 -4:00 - AST
1159
1160# Guadeloupe
1161# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1162Zone America/Guadeloupe -4:06:08 - LMT 1911 Jun 8 # Pointe a Pitre
1163 -4:00 - AST
1164
1165# Guatemala
1166# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1167Rule Guat 1973 only - Nov 25 0:00 1:00 D
1168Rule Guat 1974 only - Feb 24 0:00 0 S
1169Rule Guat 1983 only - May 21 0:00 1:00 D
1170Rule Guat 1983 only - Sep 22 0:00 0 S
1171# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1172Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5
1173 -6:00 Guat C%sT
1174
1175# Haiti
1176# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1177Rule Haiti 1983 only - May 8 0:00 1:00 D
1178Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D
1179Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S
1180Rule Haiti 1988 max - Apr Sun>=1 2:00 1:00 D
1181Rule Haiti 1988 max - Oct lastSun 2:00 0 S
1182# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1183Zone America/Port-au-Prince -4:49:20 - LMT 1890
1184 -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT
1185 -5:00 Haiti E%sT
1186
1187# Honduras
1188# Shanks says 1921 Jan 1; go with Whitman's more precise Apr 1.
1189# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1190Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr
1191 -6:00 Salv C%sT
1192
1193# Jamaica
1194
1195# From Bob Devine (1988-01-28):
1196# Follows US rules.
1197
1198# From U. S. Naval Observatory (1989-01-19):
1199# JAMAICA 5 H BEHIND UTC
1200
1201# From Shanks (1991):
1202# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1203Zone America/Jamaica -5:07:12 - LMT 1890 # Kingston
1204 -5:07 - KMT 1912 Feb # Kingston Mean Time
1205 -5:00 - EST 1974 Jan 6 2:00
1206 -5:00 US E%sT
1207
1208# Martinique
1209# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1210Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France
1211 -4:04 - FFMT 1911 May # Fort-de-France MT
1212 -4:00 - AST 1980 Apr 6
1213 -4:00 1:00 ADT 1980 Sep 28
1214 -4:00 - AST
1215
1216# Montserrat
1217# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1218Zone America/Montserrat -4:08:52 - LMT 1911 Jul 1 0:01 # Plymouth
1219 -4:00 - AST
1220
1221# Nicaragua
1222# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1223Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D
1224Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S
1225# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1226Zone America/Managua -5:45:08 - LMT 1890
1227 -5:45 - MMT 1934 Jun 23 # Managua Mean Time
1228 -6:00 - CST 1973 May
1229 -5:00 - EST 1975 Feb 16
1230 -6:00 Nic C%sT
1231
1232# Panama
1233# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1234Zone America/Panama -5:18:08 - LMT 1890
1235 -5:20 - PMT 1908 Apr 22 # Panama Mean Time
1236 -5:00 - EST
1237
1238# Puerto Rico
1239# There are too many San Juans elsewhere, so we'll use `Puerto_Rico'.
1240# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1241Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan
1242 -4:00 - AST 1942 May 3
1243 -4:00 1:00 AWT 1945 Sep 30 2:00
1244 -4:00 - AST
1245
1246# St Kitts-Nevis
1247# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1248Zone America/St_Kitts -4:10:52 - LMT 1912 Mar 2 # Basseterre
1249 -4:00 - AST
1250
1251# St Lucia
1252# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1253Zone America/St_Lucia -4:04:00 - LMT 1890 # Castries
1254 -4:04 - CMT 1912 # Castries Mean Time
1255 -4:00 - AST
1256
1257# St Pierre and Miquelon
1258# There are too many St Pierres elsewhere, so we'll use `Miquelon'.
1259# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1260Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre
1261 -4:00 - AST 1980 May
1262 -3:00 Mont PM%sT # Pierre & Miquelon Time
1263
1264# St Vincent and the Grenadines
1265# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1266Zone America/St_Vincent -4:04:56 - LMT 1890 # Kingstown
1267 -4:05 - KMT 1912 # Kingstown Mean Time
1268 -4:00 - AST
1269
1270# Turks and Caicos
1271# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1272Zone America/Grand_Turk -4:44:32 - LMT 1890
1273 -5:07 - KMT 1912 Feb # Kingston Mean Time
1274 -5:00 - EST 1979 Apr 29 2:00
1275 -5:00 US E%sT
1276
1277# British Virgin Is
1278# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1279Zone America/Tortola -4:18:28 - LMT 1911 Jul # Road Town
1280 -4:00 - AST
1281
1282# Virgin Is
1283# Zone NAME GMTOFF RULES FORMAT [UNTIL]
1284Zone America/St_Thomas -4:19:44 - LMT 1911 Jul # Charlotte Amalie
1285 -4:00 - AST